Who is to say that, in the minds of some, serious negative moral judgement is NOT rendered against those who use poor grammar? I would posit that, particularly for the spoken word (we hear more people speak than we read their writing), many lose out on opportunities they might have enjoyed had poor grammar not caused a synaptic snag in the brain of another!

I imagine it has cost jobs, potential relationships and a host of other complexities in the lives of those who have not had the benefit of a fundamental education in the grammar of their native tongue.

I think it has already caused a rather violent revolution. This is the classic story of the “haves” and the “have nots” wherein one group has the benefit of education (=money=power) and other groups, without benefit of education (which can be all too obvious when they speak) lose out on opportunities for money and power. This serves to reinforce whatever official or unofficial class system exists and is self-perpetuating through generations. The worst cases have resulted in incredible levels of violence. For example, the prisons in my state are certainly not filled with grammarians . . .

The chicken and egg part of the question is “If we all threw in the towel on grammar would things be more equal (and less violent) OR should we all work to create opportunity to benefit more people who can understand and appreciate good grammar?”